The Expeditionary Fighting Vehicle (EFV) is an armored amphibious vehicle capable of transporting troops from ships to inland objectives. The EFV includes tracks to propel the vehicle over land and water jets to propel the vehicle over water. The EFV provides operator controls which permit an operator of the EFV to manually select from a water mode, a transition mode, and a land mode of operation. In water mode, the engine produces water power to drive turbines of the water jets and propel the vehicle across water. In land mode, the engine produces land power to drive tracks and propel the vehicle over land. Further, in transition mode, the engine produces transition power to power (i) both tracks and water jets, (ii) tracks only, or (iii) water jets only as the vehicle transitions between land and water.
In one embodiment, the engine produced water power (e.g. 2700 Hp) and transition power (e.g. 1600 Hp) are both substantially greater than the land power (e.g. 850 Hp). During normal operation, the operator of the amphibious vehicle places the vehicle in a transition mode as the vehicle is approaching land and manually selects land mode upon the vehicle reaching land. However, if the operator does not manually select land mode when the vehicle transitions from water to land, the engine produced transition power exerts torque upon the transmission and components of the land propulsion assembly for which the transmission and components were not designed. Thus, continued production of transition power while the vehicle is traveling over land may result in failure of the transmission and/or land propulsion assembly due to the excess delivered power.